1. Field of the Invention
This invention relates generally to portable forced-air heaters, and more particularly to portable forced-air heaters that derive at least a portion of their electric energy required for operation of the heaters, or an accessory thereof, from an on board source.
2. Description of Related Art
Fuel-fired portable heaters such as forced-air heaters are well known in the art and find use in multiple environments. The heater typically includes a cylindrical housing with a combustion chamber disposed coaxially therein. A combustible liquid fuel from a fuel tank is atomized and mixed with air inside the combustion chamber where it is combusted, resulting in the generation of a flame. During combustion of the air/fuel mixture a fan blade is rotated by an electric motor to draw ambient air into the heater to be heated by the combustion of the air/fuel mixture. The heated air is expelled out of the heater by the continuous influx of air caused by the fan.
Traditionally, forced-air heaters have required a source of electric energy to energize the motor that rotates the fan blade and optionally to operate an ignition source that triggers combustion of the air/fuel mixture. The fan is often a heavy-duty, high output fan that consumes significant amounts of electric energy during operation thereof, and operation of the igniter consumes even more electric energy. The demand for electric energy created by operation of the fan and other electric components of forced-air heaters has required such heaters to be plugged into a conventional wall outlet supplying alternating current (“AC”) electric energy generated by a public utility. In remote environments a lengthy extension cord can establish a conductive pathway for the electric energy between a wall outlet and the location of the forced-air heater. However, at locations where a new structure is being built a conventional wall outlet is typically not available, requiring the use of a portable generator to supply the electric energy until utility-generated electric energy becomes available.
As previously mentioned, forced-air heaters are often utilized to provide heat to new construction environments for significant periods of time that can extend well into the night. After dusk, illumination of the environment in the vicinity of the forced-air heater is required to enable workers to view their worksite and avoid potentially hazardous conditions. Assuming that a conventional wall outlet is available, an extension cord can be used to conduct electric energy from the wall outlet to an on-site light stand. However, the light stand adds to the equipment that must be transported to a jobsite, and a conventional wall outlet is usually not available during the initial stages of a new construction.
Even in instances when a conventional wall outlet is available, there are normally a limited number of electric devices that can be powered by the outlet at any given time. Using adaptors to increase the number of available outlets into which an electrical device can be plugged can lead to excessive currents being drawn through an extension cord or other adaptor. Thus, there are a limited number of electrical devices that can be simultaneously powered on a new construction jobsite at any given time. This limitation is even greater when a wall outlet supplying utility-generated electricity is unavailable.
Forced-air heaters are also relatively bulky, and occupy a significant amount of storage space while not in use. Attempts to store such a heater in an alternative orientation other than its intended operational orientation in which the heater is designed to be fired in order to conserve storage space results in the liquid fuel leaking out of the heater. And although the fuel can be drained from the heater before storing it in an alternative orientation to minimize the leakage of fuel, such an option is time consuming, and is impractical for temporary storage on a daily basis.
Accordingly, there is a need in the art for a forced air heater that is operational in a remote environment in the absence of a conventional wall outlet supplying utility-generated AC electric energy. At least one electrical component of the forced air heater can be energized during operation of the heater by electric energy from an on-board source of electric energy. The forced air heater can also optionally include an electric energy outlet that can provide an interface through which an electric accessory can be energized by electric energy from the on-board energy source. Further, the forced air heater can optionally also include a light source for illuminating an environment in the vicinity of the forced air heater. Further yet, the forced air heater can optionally include a fuel-management system that minimizes leakage of a liquid fuel from the heater while stored in an alternative orientation other than the orientation in which it is to be fired.